Teaching, teasing and hidden affection

Teaching and Rage - The beginning

"For goodness sake, Alhaitham! You know damn well you can do 40 + 27 in your head!" Kaveh snapped, losing his patience.

"Senior, I don't know what you're talking about. I simply lack the proper knowledge when it comes to mathematics." Alhaitham replied, masking his smirk, struggling to hide it - but managing.

Four hours.
They'd been attempting to study for four hours, and Kaveh was about to explode with pure, unadulterated rage.
Alhaitham had come to him with a failing grade in math, and practically begged his senior to tutor him - something kaveh never thought he'd see Alhaitham do.
So, as any good senior would - Kaveh tried to teach Alhaitham. Key word, tried. Kaveh really tried. But Alhaitham wasn't doing anything except annoying him. Like now, for instance. Kaveh was trying to get Alhaitham to do some simple addition, and alhaitham decides to pick up a calculator! A calculator for 203 + 123!

"Alhaitham, put the calculator down. Now." Kaveh hissed, fists clenching, knuckles going white. Either Alhaitham was acting like a moron, or he... was a moron. And right now Kaveh couln't decide which one it was.

"I need it." Alhaitham responded bluntly, ignoring the blond completely, focusing on his oh-so-important calculator.

"You're not an idiot, Alhaitham. We both know this." Kaveh groaned, rolling his eyes.
Alhaitham didn't say a word in response, focusing on writing in his notebook, and using his calculator for simple addition. It'd been almost 20 minutes of this, and Kaveh had already had enough. He took the calculator from Alhaitham's hand and pointed at the page.
"17 + 467." He said sternly, "Without a calculator." Kaveh watched Alhaitham think for what felt like 10 minutes. And when he checked his phone - it had been 10 minutes. "Archons, Alhaitham! Can't you use your brain for this? I know kids younger than you who can do this in a flash! And don't say 'I'm not as talented as they are' because we both know you can do it, and you're just acting stupid for the sake of it!" Kaveh went on a rant for the next 15 minutes on how Alhaitham could work just fine without a calculator, and didn't need Kaveh or anyone's help to do math, and was lying for the attention. In his rant Alhaitham listened to maybe 3 of his sentences, too busying staring at his senior's pretty face.

"...Uh-huh." Alhaitham muttered every few minutes to make it look like he was actually paying attention, but absolutely wasn't. "...Can I have the calculator back?" He asked, pretending to be nonchalant.

"Will you do addition like a normal person?" Kaveh shot back, glaring at the junior.

"I suppose. Since I don't have a choice." He muttered back, a slight smile visible if you squinted really hard.

"...Here." Kaveh slid the calculator across the table to Alhaitham, not exactly enthusiastic to hand it over, having a feeling the younger male would pull something silly again.
Kaveh turned to pick a book from his bag. He turned around for maybe seven seconds. He turned back around to see Alhaitham using the calculator again. He absolutely lost it.
"For goodness sake, Alhaitham! You know damn well you can do 40 + 27 in your head!" Kaveh snapped, losing his patience.

"Senior, I don't know what you're talking about. I simply lack the proper knowledge when t comes to mathematics." Alhaitham replied, masking his smirk, struggling to hide it - but managing.

"I— You know exactly what you're doing!" Kaveh shot up from his seat, hitting his hands on the desk, slightly flustered from when Alhaitham called him "Senior". It was the tone he used. Teasing, but affectionate. It made his heart race in ways he couldn't explain.

"Do I?" He asked, unable to hide his smirk at this point, smirking at the blond sat across from him. He'd stop - for now. But there was always other times he could tease Kaveh. An opportunity struck him every day but sometimes he'd spare his senior from his endless, ruthless teasing.

"We're done here. You've been discovered. I know your little tricks. You've been failing so I can tutor you, and then you can make a fool out of me!" Kaveh exclaimed, completely and utterly enraged. They'd been here for so long that Kaveh's braid had started to loosen, slowly slipping from its ribbon with each excruciatingly long minute they spent doing simple mathematics.

"Maybe. But not so I can make a fool out of you." Alhaitham muttered, his voice genuine and laced with affection

Alhaitham wasn't quiet enough. Kaveh had heard his comment, and was definitely going to demand more from him. "Oh really? Then why else would you make me tutor you? Why not get an actual professor to assist?" Kaveh pushed for more information, wanting to know why Alhaitham would get him out of all people to tutor him.

"You still haven't figured it out, senior? I thought you were smarter than this." Alhaitham teased, smirking slightly, still trying to hide it and keep his nonchalant demeanour.

"No, I haven't. Tell it to me straight or shut your bratty mouth!" Kaveh scolded, demanding to be given answers.